EcoCheck: can the Brigalow Belt bounce back?


Leonie Seabrook, The University of Queensland; Clive McAlpine, The University of Queensland, and Martine Maron, The University of Queensland

Our EcoCheck series takes the pulse of some of Australia’s most important ecosystems to find out if they’re in good health or on the wane.

Queensland’s Brigalow Belt is among Australia’s most significant biodiversity hotspots. Extending over an area of 36.4 million hectares from Townsville down into New South Wales, it was famously where the explorer Ludwig Leichhardt travelled, prickly pear was vanquished, and the now-extinct paradise parrot once lived.

The Brigalow Belt bioregions.
Hesperian/IBRA/Wikimedia Commons

Although the region contains diverse ecosystems, from dry vine scrub to grasslands, it is named after the species of tree that once dominated: the brigalow (Acacia harpophylla). This unusual, long-lived acacia with its dark, fissured bark and distinctive silver leaves forms dense woodlands, home to unique and threatened plants and animals.

Before clearing, brigalow-dominated ecological communities covered an estimated 7.5 million ha within the Brigalow bioregion. But those vast brigalow woodlands are no longer here.

Remnant brigalow woodland, Queensland.

Sought-after soil

Since the arrival of Europeans in the 1850s, 90% of brigalow forest has been cleared. Brigalow grows on fertile, cracking clay soils – the same soils needed for agriculture. Only 790,000 ha of brigalow ecosystems remain – just over 10% of the original extent. Sixteen out of 22 ecosystems where brigalow is the dominant or co-dominant species have less than 10% left – and even those are under threat.

Clearing of brigalow for crops and pasture began soon after European settlement. Initially, the task of turning the Brigalow into a breadbasket turned out to be more challenging than the settlers expected. Brigalow trees have a well-developed lateral root system. If the tree or roots are damaged, dense “suckers” spring up. This growth stage can last for 20-30 years and is followed by a “whipstick” stage lasting another 20-30 years before mature forest is formed.

This habit made permanent removal very difficult, as suckers can occur at a density of 20,000 stems per hectare.

Very young brigalow regrowth.

Agricultural development was also delayed by the invasion by prickly pear. Between 1901 and 1925, these spiky American cacti spread across 24 million ha of Queensland and NSW. Communities and governments despaired of being able to control this weed, but by 1932 a biological control agent, the Cactoblastis moth, had almost completely destroyed prickly pear.

It was not until the 1960s – and a “perfect storm” of mechanised land clearing, favourable government policies, scientific research into brigalow control, and a push for agricultural development – that clearing could occur on a grand scale. Once the problem was cracked, clearing rates soared. At times, rates equalled those in tropical forest regions such as the Amazon and Southeast Asia.

Legacy of loss

Today, the Brigalow Belt is a precious, but threatened, reservoir of endemic diversity. Brigalow woodland is nationally endangered, with severe consequences for the animals of the Brigalow Belt. Four species, including the paradise parrot, are extinct. Another 17 are on the threatened species list in either NSW or Queensland.

The Brigalow Belt is home to the threatened golden-tailed gecko.
Dave Fleming/Atlas of Living Australia

Remaining patches of brigalow are often modified by the removal of understorey shrubs and fallen timber. This affects habitat structure for reptiles and woodland birds in particular, reducing population sizes and encouraging aggressive competitors such as the noisy miner.

Many exotic species have been introduced, including pasture grasses. The most widespread of these is buffel grass, which has been a boon for pastoralists. Unfortunately, its invasion of remnant brigalow and contribution to fuelling bushfires has had dramatic effects on plant and animal biodiversity.

The Brigalow Belt is also home to 13 reptile species that are found only in this region, and another 14 for which the region is their main home. Eleven of the 148 reptile species found in the Brigalow Belt are threatened.

But the very suckering habit that made brigalow trees so difficult to clear in the early days may now be its salvation. Although brigalow regrowth is initially very different from old-growth woodland, if it is allowed to persist, the vegetation structure becomes more and more complex and diverse. After 30-50 years, mature regrowth can support as many bird species as old-growth woodland.

The future of the brigalow

Only 1% of the remaining brigalow woodland is in protected areas. The rest is highly fragmented, existing mainly as tiny patches, linear strips along roads and fence lines, and areas of regrowth.

Land-use change for agriculture, coal mining and coal seam gas extraction continues to nibble away at remaining brigalow ecosystems, despite protection by state and federal laws. In 2013-14, 44% of all woody vegetation clearing in Queensland occurred in the Brigalow Belt.

Legislation controlling most broadscale clearing of remnant native vegetation was introduced through the Queensland Vegetation Management Act 1999. This phased out clearing of remnant vegetation by December 2006. In 2008, recognising that the only way to recover threatened ecosystems like brigalow forest was to increase their extent, mature “high-value” regrowth of threatened ecosystems was also protected.

But in 2013 came a setback, with the introduction of the Vegetation Management Framework Amendment Act 2013, which allowed for much more vegetation clearing and removed the protections for high-value regrowth. Laws to reinstate those protections are before the Queensland Parliament.

The opportunity to recover the brigalow will not last forever. With repeated clearing, burning and cultivation, these forests could eventually disappear for good. But in those areas where some resilient regrowth remains, there is potential for recovery.

In 2009, there was an estimated 7,226 square km of regrowth, comprising a range of structures from juvenile bushes (aged 5-10 years) to almost mature stands (aged 30-50 years). This regrowth provides a promising and cost-effective way to increase habitat area for both fauna and flora, and reduce their risk of extinction.

To do this, however, we need to find ways to make retention of brigalow regrowth attractive and valuable to landholders, through stewardship schemes or carbon offsets. Only then might the Brigalow Belt bounce back.

Are you a researcher who studies an iconic Australian ecosystem and would like to give it an EcoCheck? Get in touch.

The Conversation

Leonie Seabrook, Landscape Ecologist, The University of Queensland; Clive McAlpine, Senior Research Fellow in Ecology, The University of Queensland, and Martine Maron, ARC Future Fellow and Associate Professor of Environmental Management, The University of Queensland

This article was originally published on The Conversation. Read the original article.

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Queensland land clearing is undermining Australia’s environmental progress


Martine Maron, The University of Queensland; Bill Laurance, James Cook University; Bob Pressey, James Cook University; Carla P. Catterall, Griffith University; Clive McAlpine, The University of Queensland; Hugh Possingham, The University of Queensland; James Watson, The University of Queensland; Jonathan Rhodes, The University of Queensland; Kerrie Wilson, The University of Queensland, and Marc Hockings, The University of Queensland

Land clearing has returned to Queensland in a big way. After we expressed concern that policy changes since 2012 would lead to a resurgence in clearing of native vegetation, this outcome was confirmed by government figures released late last year.

It is now clear that land clearing is accelerating in Queensland. The new data confirm that 296,000 hectares of bushland was cleared in 2013-14 – three times as much as in 2008-09 – mainly for conversion to pastures. These losses do not include the well-publicised clearing permitted by the government of nearly 900 square kilometres at two properties, Olive Vale and Strathmore, which commenced in 2015.

Map showing the amount of habitat for threatened species cleared between 2012 and 2014.
WWF

Alarmingly, the data show that clearing in catchments that drain onto the Great Barrier Reef increased dramatically, and constituted 35% of total clearing across Queensland in 2013-14. The loss of native vegetation cover in such regions is one of the major drivers of the deteriorating water quality in the reef’s lagoon, which threatens seagrass, coral reefs, and other marine ecosystems.

The increases in land clearing are across the board. They include losses of over 100,000 hectares of old-growth habitats, as well as the destruction of “high-value regrowth” – the advanced regeneration of endangered ecosystems.

These ecosystems have already been reduced to less than 10% of their original extent, and their recovery relies on allowing this regrowth to mature.

Alarmingly, our analysis of where the recent clearing has occurred reveals that even “of concern” and “endangered” remnant ecosystems are being lost at much higher rates now than before.

While this level of vegetation loss and damage continues apace, Australia’s environmental programs will fall well short of achieving their aims.

Nutrient and sediment runoff, exacerbated by land clearing, is one of the major ongoing threats to the Great Barrier Reef.
Great Barrier Reef image from http://www.shutterstock.com

Neutralising our environmental programs

Land clearing affects all Australians, not just Queenslanders. Australia spends hundreds of millions of dollars each year trying to redress past environmental damage from land clearing. Tens of thousands of volunteers dedicate their time, money and land to the effort.

But despite undeniable local benefits of such programs, their contribution to national environmental goals is undone, sometimes many times over, by the damage being done in Queensland.

Take the federal government’s 20 million trees program. At a cost of A$50 million, it aims to replace 20 million trees by 2020 to redress some of the damage from past land clearing.

Yet just one year of increased land clearing in Queensland has already removed many more trees than will be painstakingly planted during the entire program.

The Australian government’s Emissions Reduction Fund (ERF) is paying billions of dollars to reduce carbon emissions from industry. But the carbon released from Queensland’s land clearing in 2012-2014 alone is estimated at 63 million tonnes, far more than was purchased under the first round of the ERF (at a cost to taxpayers of A$660 million).

Species cannot recover if their habitat is being destroyed faster than it is being restored. But under Caring for our Country and Biodiversity Fund grants, the extent of tree planting to restore habitat across Australia reported since 2013 is just over 42,000 hectares – an order of magnitude less than what was cleared in Queensland alone in just two years.

And it will be many decades before these new plantings will provide anything like the environmental benefits of mature native vegetation.

Glossy black-cockatoos are one of the species threatened by Queensland land clearing.
David Cook/Flickr, CC BY-NC

Land clearing between 2012 and 2014 in Queensland is estimated to have wiped out more than 40,000 hectares of koala habitat, as well as habitat for over 200 other threatened species. Clearing, along with drought (which is also made worse by clearing), is the major cause of an 50% decline in koalas of south-west and central Queensland since 1996.

The loss of remnant habitat, especially from forests along waterways, means more habitat fragmentation. This is a further threat to many species of wildlife, and it hampers our ability to adapt to a rapidly changing climate.

The federal government has committed hundreds of millions of dollars to improve reef water quality. Yet ongoing land clearing in reef-draining catchments will reverse many of the gains these programs aim to achieve. Last year, Queensland’s Auditor-General reported that stronger legislation would be essential to reducing harmful catchment runoff to the Great Barrier Reef.

Prevention is better than cure

We live in an era of tightening carbon budgets, declining land-production capacity and rapidly deteriorating biodiversity, including in iconic places such as Great Barrier Reef. The evidence is clear that we cannot continue to degrade our environment without severe consequences.

It is far more efficient to prevent environmental damage than to try to reverse it later.

Koalas have declined 50% in Queensland over the past 15-20 years.
Mike Locke/Flickr, CC BY-ND

For example, the cost of stabilising river-banks following deforestation can range from A$16,000 to A$5 million per kilometre. Natural ecosystems contribute enormously to the economy in ways that are often unrecognised.

We are running up a large environmental debt that will eventually have to be paid by all Australians, one way or another.

And some damage, like the loss of a species, is irreversible.

Previous native vegetation laws had successfully reduced land clearing, but were reversed in 2013 by the former Newman government.

The current Palaszczuk government in Queensland has repeated its election promise to re-strengthen native vegetation protections. The amendment bill is due to be introduced to parliament within weeks.

But the minority government relies on the votes of cross-benchers to pass its legislation–so for now, the future of some of Australia’s most precious environmental assets remains uncertain.

The Conversation

Martine Maron, Associate Professor of Environmental Management, The University of Queensland; Bill Laurance, Distinguished Research Professor and Australian Laureate, James Cook University; Bob Pressey, Professor and Program Leader, Conservation Planning, ARC Centre of Excellence for Coral Reef Studies, James Cook University; Carla P. Catterall, Professor in ecology and environment, Griffith University; Clive McAlpine, Senior Research Fellow in Ecology, The University of Queensland; Hugh Possingham, Director ARC Centre of Excellence for Environmental Decisions, The University of Queensland; James Watson, Associate professor, The University of Queensland; Jonathan Rhodes, Associate Professor, The University of Queensland; Kerrie Wilson, Associate Professor and ARC Future Fellow, The University of Queensland, and Marc Hockings, Professor of Environmental Management, The University of Queensland

This article was originally published on The Conversation. Read the original article.

Dominican Republic: Loma Charco Azul Biological Reserve – Clearing Begins


The link below is to an article reporting on land clearing in the Loma Charco Azul Biological Reserve in the Dominican Republic.

For more visit:
http://news.mongabay.com/2013/0723-hance-loma-charco-azul.html

Australia: Queensland – Land Clearing Bill Passed


The link below is to an article reporting on a land clearing bill that has passed the Queensland Parliament.

For more visit:
http://www.couriermail.com.au/news/queensland/controversial-vegetation-laws-passed-in-parliament-last-night-will-increase-land-clearing-say-conservationists/story-e6freoof-1226647966289

Australia: Queensland – Land Clearing


The link below is to an article that reports on land clearing activities in Queensland and offers you a way to participate in protests against it.

For more visit:
http://support.wwf.org.au/landclearing.html